A popular type of towing hitch assembly is a fifth wheel hitch assembly. This type of towing hitch assembly utilizes a horseshoe-shaped coupling device, or fifth wheel, on the rear of the towing vehicle to secure a coupling pin (or kingpin) disposed at the front of the load to be towed. In order to secure the towed load, the coupling pin is inserted into the fifth wheel, which is then rotated, thereby locking the coupling pin securely in place for towing.
Where the fifth wheel hitch assembly is capable of longitudinal translation relative to the towing vehicle, the hitch assembly is a sliding hitch assembly. The longitudinal movement of the fifth wheel assembly allows the fifth wheel, and correspondingly the coupling pin secured by the fifth wheel, to be selectively positioned relative to the towing vehicle. For example, the fifth wheel may be located substantially above the towing vehicle's rear axle during normal towing, and then selectively displaced in the direction of the rear end of the towing vehicle in order to permit increased clearance between the towing vehicle and trailer. This increased clearance in turn offers greater maneuverability, as the towing vehicle and trailer may perform tighter turns due to the increased clearance.
Selected examples of towing hitch assemblies are disclosed in U.S. Pat. No. 5,707,070, U.S. Pat. No. 5,772,229, U.S. Pat. No. 6,386,570, U.S. Pat. No. 6,557,883, U.S. Pat. No. 6,682,089, U.S. Pat. No. 6,685,210 and U.S. Pat. No. 7,584,982 and U.S. Patent Publication No. US20110109061. The disclosures of these and all other publications referenced herein are incorporated by reference in their entirety for all purposes.